Slate's Medical Examiner: Xenical OTCA new weight-loss drug is about to be approved by the Federal Drug Administration (FDA) for over-the-counter sale. Madeleine Brand talks with Dr. Sydney Spiesel, a Connecticut pediatrician and Slate contributor, about the pros and cons of orlistat, currently marketed as the prescription drug Xenical.

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A new weight-loss drug is about to be approved by the Federal Drug Administration (FDA) for over-the-counter sale. Madeleine Brand talks with Dr. Sydney Spiesel, a Connecticut pediatrician and Slate contributor, about the pros and cons of orlistat, currently marketed as the prescription drug Xenical.

ALEX CHADWICK, host:

This is Day to Day from NPR News. I'm Alex Chadwick.

MADELEINE BRAND, host:

And I'm Madeline Brand. Time now for our regular look at health news. Here's a magic bullet a lot of people would love, a pill that lets you eat fatty foods and still lose weight. The FDA's considering approving such a pill for over-the-counter use, but these kinds of pills have come and gone before. Joining us to talk about this latest weight loss promise is Doctor Sydney Spiesel, pediatrician and professor at the Yale Medical School. And Doctor Spiesel welcome back to Day to Day.

Dr. SYDNEY SPIESEL (Yale Medical School): Thank you. Hi.

BRAND: Well, tell us about this drug, it's called Orlistat.

Dr. SPIESEL: You swallow it and it enters the intestinal contents and it blocks the activity of an enzyme called lipase. And lipase is important for taking fat and putting it in a form that can be absorbed. So if lipase is inactivated then the fat can't be absorbed and it passes right through us. And that's one theory of the way Orlistat works.

BRAND: So you could eat a cupcake and it would not show up on your hips, it would just go somewhere else.

Dr. SPIESEL: Yeah, And we'll talk in a minute about where it might go, but, yeah, that's actually the idea of Orlistat, that if you can't absorb fat then you're going to lose weight. Although if you actually look at the recommendations in the studies, they don't really allow you to eat cupcakes. The way the stuff has always been tested and the way it seems to work best is with, I'm sorry to say, a reduced fat diet in order for it to work properly.

BRAND: Well, let's talk about the side effects. How does it work?

Dr. SPIESEL: Oh, the side effects are a problem. There are some medical side effects. I mean, one of them is that we need fat to absorb fat soluble vitamins like vitamin A and vitamin D. So, people who are taking Orlistat need to have excess doses of these nutritional materials. But there are some side effects that are less pleasant. The unabsorbed fat leads to gas, flatulence, diarrhea, increased bowel movements, and even, how to put this delicately, anal leakage of oily material.

BRAND: Ugh, yeah, unpleasant.

Dr. SPIESEL: Very unpleasant, although, I'd like to propose an idea.

BRAND: Ok.

Dr. SPIESEL: It may be that the idea that once you are taking this medication and it produces these frankly very unpleasant side effects that maybe you get kind of negatively conditioned and you learn not to eat fatty foods. And maybe that's part of the mechanisms that it would lead to a decreased intake of fatty foods, because otherwise you're going to have these kind of awful symptoms. And there's a kind of precedent for that in medicine. There's a drug that has been used to treat alcoholism called Antabuse, and what Antabuse does it changes the metabolism of alcohol so that people who drink and take Antabuse feel horribly, horribly sick. And so there are alcoholics who just take a dose of Antabuse everyday and that blocks any strong impulse to drink because the effects are so ghastly. I don't know if that's true with Orlistat, but I sort of suspect it might be.

BRAND: You know, we have heard, though, after these weight loss pills and medication, after they are approved, of side effects that are actually a lot more dangerous, Phen-Fen for example.

Dr. SPIESEL: Sure. There's a risk for every--with any drug that's being introduced. One of the side effects, which nobody actually likes to talk about, for all of these medications, is that once you stop taking them people start gaining weight again.

BRAND: So then we're back to the old tried and true, diet and exercise.

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